Home
Class 12
PHYSICS
What should be the radius of a planet wi...

What should be the radius of a planet with mass equal to that of earth and escape velocity on its surface is equal to the velocity of light. Given that mass of earth is `M=6xx10^(24)kg`.

A

6mm

B

9mm

C

18mm

D

3mm

Text Solution

Verified by Experts

The correct Answer is:
B
`v_(c)=sqrt((2GM)/(R))rArrR=(2GM)/(v_(e)^(2))approx 9mm`
Promotional Banner

Topper's Solved these Questions

  • TEST PAPERS

    ALLEN|Exercise PAPER 2|60 Videos

  • TEST PAPERS

    ALLEN|Exercise PAPER 3|100 Videos

  • TEST PAPER 4

    ALLEN|Exercise PHYSICS|45 Videos

  • UNIT & DIMENSIONS, BASIC MATHS AND VECTOR

    ALLEN|Exercise Exercise (J-A)|7 Videos

Similar Questions

Explore conceptually related problems

Mass and radius of a planet are two times the value of earth. What is the value of escape velocity from the surface of this planet?

The escape velocity of a body from the surface of the earth is equal to

If the escape velocity of a planet is 3 times that of the earth and its radius is 4 times that of the earth, then the mass of the planet is (Mass of the earth = 6 xx 10^24 kg )

The mass of Saturn is 95 times that of earth and radius is 9.5 times the radius of earth. What will be escape velocity on the surface of saturn if the escape velocity on earth's surface is 11.2 kms^(-1) ?

If the radius of the earth shrinks by 0.2% without any change in its mass, the escape velocity from the surface of the earth

What is the maximum height attained by a body projected with a velocity equal to one- third of the escape velocity from the surface of the earth? (Radius of the earth=R)

What is the magnitude of the gravitational force between the Earth and a 1kg object on its surface ? (Mass of the earth is 6xx10^(24) kg and radius of the Earth is 6.4xx10^(6) m) .

ALLEN-TEST PAPERS-MATHS
  1. What should be the radius of a planet with mass equal to that of earth...

    Text Solution

    |

  2. If complex number z(zne2) satisfies the equation z^(2)=4z+|z|^(2)+(16)...

    Text Solution

    |

  3. Let omegabe a complex number which satisfies iomega=(u^(2)-1)/(u^(2)+...

    Text Solution

    |

  4. If the function f(x)={{:((1+cospix)/(pi^(2)(x+1)^(2)),",",xlt-1),(ax...

    Text Solution

    |

  5. The value of the following limit lim(ntooo) n(n+1)(ln(1+(1)/(n))-sin((...

    Text Solution

    |

  6. number of solutions for x between 3 and 15 if int(0)^(x)[t]dt=int(0)^(...

    Text Solution

    |

  7. If the length of perpendicular from (0,0,0) to the plane ax+by+cz+d=0 ...

    Text Solution

    |

  8. A transversal cuts side AB and AD and diagonal AC of parallelogram ABC...

    Text Solution

    |

  9. Consider curve y=(1+x)^(y)+sin^(-1)(sin^(2)x). Which of the following ...

    Text Solution

    |

  10. The x-intercept of the tangent to a curve is equal to the ordinate of ...

    Text Solution

    |

  11. Suppose y=f(x)andy=g(x) are two functions whose graph intersect at th...

    Text Solution

    |

  12. A function y=f(x) satisfies f"(x)=-(1)/(x^(2))-pisin(pix),f(2)=pi+(1)...

    Text Solution

    |

  13. Let(1+X^(2))^(2)(1+X)^(n)=sum(k=0)^(n+4)a(k)X^(k).ifa(1),a(2),a(3) ar...

    Text Solution

    |

  14. If f(x) is double differentiable function such that |f"(x)|le5 for ea...

    Text Solution

    |

  15. overline(x)andoverline(y) be two variable vectors satisfying simultan...

    Text Solution

    |

  16. The curve defined by sqrt((x)/(a))+sqrt((y)/(b))=1 gives a part of pa...

    Text Solution

    |

  17. The curve defined by sqrt((x)/(a))+sqrt((y)/(b))=1 gives a part of pa...

    Text Solution

    |

  18. In a problem of differentiation of (f(x))/(g(x)), one student writes ...

    Text Solution

    |

  19. In a problem of differentiation of (f(x))/(g(x)), one student writes ...

    Text Solution

    |